JP5850949B2 - Isomerization catalyst - Google Patents

Description

  Embodiments of the present invention are directed to isomerization catalysts and methods for their production. More specifically, embodiments of the present invention are directed to a 1-butene isomerization catalyst comprising MgO, a metal silicate clay binder, and a stabilizer.

MgO tablets are used as a cocatalyst in the metathesis reaction of butene with ethylene to form propylene. The metathesis reaction for forming propylene includes the following reactions.
(1) CH ₂ = CH ₂ + CHCH ₃ = CHCH ₃ ← → 2CH ₃ CH = CH ₂
(Ethylene) (2-Butene) (Propylene)

(2) CH ₂ = CHCH ₂ CH ₃ + CHCH ₃ = CHCH ₃ ← → CH ₃ CH = CH ₂ + CH ₂ = CH (CH ₂ ) ₂ CH ₃
(1-butene) (2-butene) (propylene) (1-pentene)

(3) (CH ₃ ) ₂ C═CH ₂ + CHCH ₃ = CHCH ₃ ← → CH ₃ CH═CH ₂ + (CH ₃ ) ₂ C = CHCH ₃
(Isobutene) (2-butene) (propylene) (2-methyl-2-butene)

MgO achieves isomerization from 1-butene to 2-butene, H ₂ O, CO ₂ , oxygenates (such as methyl tertiary butyl ether or MTBE), sulfur compounds, nitrogen compounds, heavy metals, and the like Adsorb toxins in the feed stream.

An isomerization catalyst in the form of a tablet exhibits a crushing strength that allows the catalyst to withstand the pressures and stresses applied to the catalyst during use. However, the manufacture of tablets is expensive and time consuming. In addition, the formation of tablets with complex shapes is difficult or impossible.
Therefore, there is a need for an isomerization catalyst that can be provided in a form different from tablets and that maintains acceptable isomerization activity after aging. There is also a need for an isomerization catalyst that exhibits acceptable crush strength and thereby can withstand the pressure of the carbohydrate flow rate in the catalyst system as well as the stress applied to the catalyst when it is packed into the reactor. ing.

  As used herein, the term “crush strength” shall refer to a single piece crush strength or piece crush strength. The crushing strength can be defined as the resistance to the compressive force of the formed catalyst. The measurement of crush strength aims to provide an indication of the ability of the catalyst to maintain its physical integrity during processing and use. Fragment crush strength is the ability to place an individual catalyst, whether in an extrudate, tablet, or other form, between two planes and apply a compressive load to the catalyst or to the catalyst via the two planes. It can be measured by measuring the force required to crush the fragment using the transducer.

One or more embodiments of the invention relate to a catalyst provided as an extrudate. In such embodiments, processing of MgO or Mg (OH) ₂ is required to form MgO into the extrudate because it is provided as a powder.

A first aspect of the invention relates to an extrusion catalyst comprising MgO, a metal silicate clay binder, and one or more of ZrO ₂ , a tetravalent rare earth metal, and a trivalent rare earth metal, the catalyst Exhibits a fragment crush strength of at least 2.0 lbs / mm. In one or more embodiments, the extrusion catalyst exhibits an unused isomerization rate and post-aging performance after aging at 650 ° C. for 24 hours, wherein the post-aging isomerization rate is a measure of the unused isomerization rate. At least 50%. In one variation, the unused isomerization rate and post-aging isomerization rate of the extrusion catalyst disclosed herein includes the rate of isomerization from 1-butene to 2-butene.

  In one or more variations, MgO is present in the extrusion catalyst in an amount ranging from about 0.1% to 90% by weight. In a specific embodiment, MgO can be present in an amount of at least 50% by weight. Alternatively, MgO may be present in an amount ranging from about 70% to about 90% by weight, or more specifically about 80% by weight.

  Suitable metal silicate clay binders may include layered particles having a diameter and thickness aspect ratio in the range of 25 to 50, and a strong negative charge on the particle surface and a weak positive charge on the edge of the particle. . In one or more embodiments, the metal silicate clay binder may comprise a synthetic metal silicate. In one variation, the synthetic metal silicate clay binder comprises synthetic hectorite.

  In one or more embodiments, the metal silicate clay binder may be present in an amount ranging from 1% to 20% by weight. In a more specific embodiment, the metal silicate clay binder may be present in an amount ranging from about 5% to about 20% by weight. In an even more specific embodiment, the metal silicate clay binder may be present in an amount ranging from about 8 wt% to about 12 wt%, or may be present in an amount of about 10 wt%.

ZrO _2, tetravalent rare earth metals, and / or trivalent rare earth metal, in the range of 1 wt% to 20 wt%, may be present in one or more variations of the extrusion catalyst. Examples of suitable trivalent rare earth metals include one or more of La, Ce, Pr, and Nd. ZrO ₂ may be present in the extrusion catalyst in an amount up to about 40% by weight. In more specific embodiments, ZrO ₂ may be present in an amount ranging from about 5 wt% to about 15 wt%, or more specifically about 10 wt%.

The second aspect of the invention relates to a method of forming a 1-butene isomerization catalyst. In one or more embodiments, the method comprises mixing an MgO source, a metal silicate clay binder, and one or more of a ZrO ₂ precursor, a tetravalent rare earth metal, and a trivalent rare earth metal; Forming a first mixture and adding water to the first mixture to form a second mixture may be included. The method also extrudes the second mixture to exhibit a single piece crush strength of at least 2.0 lbs / mm and aging after aging at 650 ° C. for a fresh isomerization rate and 24 hours Including extrudates exhibiting post performance, the post-aging isomerization rate is at least 50% of the unused isomerization rate.

In one embodiment, the method may employ ZrO ₂ , a tetravalent rare earth metal, and a trivalent rare earth metal selected from one of zirconium carbonate, zirconium acetate, zirconium nitrate, and combinations thereof. In one variation, the metal silicate clay binder may be present in an amount ranging from about 5% to 20% by weight.

In one or more embodiments, a method of forming a isomerization catalyst of 1-butene, MgO source, metal silicate clay binders, and ZrO _2, 1 of the tetravalent rare earth metals, and trivalent rare earth metal One or more may be dry mixed. In one variation of the method, ZrO _2, tetravalent rare earth metals, and trivalent rare earth metal may be provided in solution form.

FIG. 1 illustrates the unused and post-aging conversion of 1-butene at ambient pressure, WHSV = 45 hours ⁻¹ , and crushing strength of isomerization catalysts according to embodiments of the present invention and known isomerization catalysts according to the prior art. To do.

  Before describing some exemplary embodiments of the present invention, it is to be understood that the present invention is not limited to the details of the structure or process steps set forth in the following detailed description. The invention is capable of other embodiments and of being practiced or carried out in various ways.

  A first aspect of the invention relates to an extruded isomerization catalyst comprising MgO, a metal silicate clay binder, and a stabilizer. The present invention is not limited to the shape of certain extrudates. Non-limiting examples of shapes that can be formed by extrusion include cylindrical extrudates, trilobe, quadrilobal, hollow cylinders, star shapes, and the like. In one or more embodiments, MgO is present in the extrudate in an amount of at least 50 wt% and up to about 90 wt%. In one or more embodiments, MgO is present in the extrudate in an amount ranging from about 70% to about 90% by weight. In a specific embodiment, MgO can be present in an amount of about 80% by weight. MgO is provided as magnesium oxide powder or as magnesium hydroxide, magnesium carbonate, or the like and can be further processed with other components to form extrudates.

  Metal silicate clay binders are provided to accommodate the lack of bonds found in MgO-containing catalysts that do not employ metal silicate clay binders. Metal silicate clay binders have been found to bind MgO and other components without sacrificing or adversely affecting the activity of the material in the isomerization reaction. In one or more embodiments, the metal silicate clay binder may be present in an amount ranging from about 0.1 wt% to about 40 wt%. In one variation, the metal silicate clay binder is in an amount in the range of about 5 wt% to about 25 wt%, or more specifically in the range of about wt% to about 20 wt%, and even more specific. May be present in an amount of about 10% by weight.

  In one or more embodiments, the metal silicate clay binder may include a layered structure. In one or more specific embodiments, the metal silicate clay binder may include a metal silicate, and even more specific embodiments may include magnesium silicate or aluminum magnesium silicate. The metal silicate clay binder can be selected from the group of montmorillonite, saponite, nontronite, beidellite, smectite (including hectorite), stevensite, magadiite, mica mineral (including illite). In a specific embodiment, the metal silicate clay binder is magnesium silicate clay or aluminum magnesium silicate clay. In a more specific embodiment, the metal silicate clay binder is smectite, and in a more specific embodiment, the metal silicate clay binder is hectorite. In an even more specific embodiment, the metal silicate clay binder is a synthetic clay binder, more specifically a synthetic hectorite clay binder, and even more specifically, Laponite®. Trademark). Synthetic metal silicate clay binders may be preferred because certain impurities in the natural clay may not adversely affect performance, but embodiments of the present invention may adversely affect the rheological properties of the extrudate mixture. Natural clay is included to the extent that it does not. The clay nanoparticles (C) may have an average particle size of 5 to 500 nm, preferably 5 to 100 nm, more preferably 5 to 50 nm. Laponite® is a synthetic disc-shaped silicate with a thickness of about 1 nm and a diameter of 25 nm. In aqueous dispersion, Laponite® has a strong negative charge on its face and a weak localized positive charge on its edge. The surface charge on such nanoparticles results, for example, in the formation of an electric double layer of Na + ions in aqueous solution. Thus, according to one aspect of the present invention, the metal silicate clay binder has a diameter in the range of about 25 to about 500, more specifically about 25 to 100, and even more specifically about 25 to 50. And a metal silicate clay binder having a thickness aspect ratio. In one or more embodiments, a clay binder having such an aspect ratio has a strong negative surface charge and a weak localized positive charge at its edges. Laponite® binder is available from Rockwood Additives Ltd., Cheshire, UK. Available under the trade name Laponite®. As explained in more detail below, the metal silicate clay binder functions as a sufficient binder without substantially adversely affecting the crush strength or activity of the catalyst.

  One or more preferred example layered structures of metal silicate clay binders form a “roof over sand” structure when dispersed in water and other additives to form a gel. The above-mentioned disk-shaped crystal is possible. In a “sand tower” structure, the disk-shaped particles include a face and an edge, and the face has a different charge than the edge. In one or more embodiments, the edge of the particle has a small localized positive charge and the surface has a negative charge. Thus, under appropriate conditions (eg, in the absence of salt or surfactant), when added to an aqueous solution, a weak positive charge on the edge of the particle is associated with the negative or surface surface of the adjacent particle. It interacts and thus forms a tower structure on the sand, providing a high thixotropic gel. “Sand Tower” structures can also break or disperse under shear stress, but reform when the shear stress is removed. Thus, the material becomes fluid under shear in the extruder but forms a stable structure after extrusion and drying.

The extrusion catalyst of one or more embodiments can include a stabilizer. In one or more embodiments, the stabilizing agent, ZrO _2, may include tetravalent rare earth metal, a trivalent rare earth metal, and combinations thereof. In one or more embodiments, the stabilizer excludes or is substantially free of any intentionally added SiO ₂ and / or Al ₂ O ₃ . The stabilizer may be present in one or more embodiments in an amount ranging from about 5% to about 40% by weight. In one variation, the stabilizer may be present in an amount ranging from about 5 wt% to about 20 wt%, or more specifically about 10 wt%.

One or more embodiments of the present invention may incorporate ZrO ₂ as a stabilizer. In one or more variations, ZrO ₂ can be provided in solution form. For example, ZrO ₂ can be provided as a zirconium carbonate containing solution, a zirconium acetate containing solution, and a zirconium nitrate containing solution, as well as other known zirconium containing solutions. In such embodiments, the zirconium-containing solution is provided along with the rest of the components, provides extrudate in a stabilizer containing ZrO _2. In one or more embodiments, ZrO ₂ can be provided in a solid form such as a powder or paste. As such, zirconium can be added in the form of hydrated oxides or hydroxides, or as zirconium carbonate powder or paste. ZrO ₂ may be present in an amount up to about 40% by weight. In one variation, ZrO ₂ may be present in an amount ranging from about 5 wt% to about 15 wt%, or more specifically in an amount of about 10 wt%.

  Examples of trivalent and tetravalent rare earth metals that can be employed include cerium, prasedim, neodymium, and lanthanum.

  The isomerization catalyst embodiments described herein can be employed to convert 1-butene to 2-butene. In one or more embodiments, the isomerization catalyst described herein maintains at least a predetermined isomerization rate after aging. For example, the isomerization catalyst described herein can exhibit an unused isomerization rate and a post-aging isomerization rate that is at least 50% of the unused isomerization rate. Aging of the catalyst occurs when the material is used for a long time and is repeatedly regenerated in the process. In an accelerated aging procedure, therefore, the catalyst is exposed to a temperature of 650 ° C. in static air for a period of 24 hours. In one or more specific embodiments, the isomerization catalyst described herein is at least 60% of the unused isomerization rate, or more specifically, at least 65% of the unused isomerization rate. It exhibits an isomerization rate after aging.

  In one or more embodiments, the isomerization catalyst described herein exhibits a fragment crush strength of at least 1.5 lbs / mm (0.68 kg / mm). In one or more embodiments, the isomerization catalyst exhibits a fragment crush strength of at least 2.0 lbs / mm (0.91 kg / mm) or at least 2.5 lbs / mm (1.13 kg / mm). As used herein, the term “crush strength” is intended to include the resistance of the formed catalyst to compressive forces. In other words, the catalyst exhibits a crushing strength that provides an indication of its ability to maintain its physical integrity during processing and use. In the embodiments described herein, fragment crush strength was measured by placing individual cylindrical catalyst pieces between dies having an area approximately 0.125 inches (3 mm) wide. The force required to crush the piece between the dies was measured by a force transducer.

  The isomerization catalyst described herein is extruded or provided as an extrudate. Although known isomerization catalysts are provided in tablet form, tablet formation has been found to be costly and time consuming. The geometry of the tableted catalyst is further limited. Extrusion formation of the isomerization catalyst provides a more efficient and cost effective alternative and provides an isomerization catalyst that exhibits the desired fragment crush strength and isomerization rate after aging. Moreover, the extrudate provides the ability to provide different geometries, which can improve or otherwise affect crush strength and isomerization activity. In one or more embodiments, the isomerization catalyst described herein may have a diameter ranging from about 0.375 inches (9.525 mm) to about 0.0625 inches (1.5875 mm).

  A second aspect of the invention relates to a method of forming an isomerization catalyst as described herein. In one or more embodiments, the Mg compound, binder, and stabilizer are mixed to form a first mixture. Water can be added to the second mixture to form a second mixture, which is then extruded to form an extrudate. In one or more embodiments, the first mixture includes a dry mixture. Otherwise, as described herein, the first mixture comprises a stabilizer solution, such as zirconium acetate, zirconium carbonate, and, after dry mixing the MgO source compound and the metal silicate clay binder, It can be formed by adding zirconium nitrate. Other stabilizers can be provided in solution or as a dry component with the MgO source compound and a synthetic binder. In one or more alternative embodiments, the MgO source compound and / or the metal silicate clay binder is a stabilizing agent without first dry mixing the MgO source compound and / or the metal silicate clay binder. Can be combined with a solution.

  The following non-limiting examples serve the purpose of illustrating various embodiments of the invention.

  Examples of isomerization catalysts AJ were formed. Examples AG and J are comparative examples, and Example I is an invention example. Fragment crush strength, unused isomerization rate, and post-aging isomerization rate were measured for each of the isomerization catalysts AJ.

  Isomerization catalysts A and B contained MgO subject to tablet forms of different purity magnesium oxide. Both types of tablets were produced commercially. Isomerization catalysts A and B were substantially free of any intentionally added stabilizer or binder. Isomerization catalyst A had a diameter of about 5 mm and isomerization catalyst B had a diameter of about 3 mm. Isomerization catalysts A and B were formed into tablets using known powder molding press methods.

Isomerization catalyst C contained MgO and alumina in an amount of about 10% by weight. The composition for isomerization catalyst C was formed by adding a 20 wt% boehmite solution to Mg (OH) ₂ in deionized water to form an extrudable mixture. Boehmite is available under the trade name DISPAL® 11N7-80 from Sasol Germany, Hamburg, Germany. The composition was extruded and had a diameter of about 3 mm. The extruded material was dried at 120 ° C. for 8 hours and calcined at 500 ° C. for 2 hours in a static muffle furnace.

Isomerization catalyst D contained MgO and ZrO ₂ in an amount of about 20% by weight. Composition for the isomerization catalyst D in order to form the extrudable mixture, zirconium carbonate solution containing ZrO ₂ of 20.3% by weight 51.7% of the hydroxide containing ZrO ₂ Formed by mixing zirconium-containing solution, water, and Mg (OH) ₂ . The ZrO ₂ solution employed for the isomerization catalyst D can be obtained from Mangnes Elecktron Ltd. of Manchester, UK. Available under the trade name BACOTE®. Isomerization catalyst D was extruded and had a diameter of about 3 mm. The material was dried and fired as in Example C above.

Isomerization catalyst E contained MgO and SiO ₂ in an amount of about 10% by weight. The composition for isomerization catalyst E was formed by mixing a colloidal silica suspension containing 30 wt% silica suspended in water with Mg (OH) ₂ and water. Suitable colloidal silicas are described in Columbia, Maryland, U.S.A. S. A. W. R. Grace and Co. Available under the trade name LUDOX® AS-30. The composition was then extruded and had a diameter of about 3 mm. The material was dried and fired as in Example C above.

Isomerization catalyst F included MgO, ZrO ₂ , and SiO ₂ . ZrO ₂ was present in an amount of about 10% by weight and SiO ₂ was present in an amount of about 10% by weight. The composition for isomerization catalyst F was 34% by weight suspended in water with Zr—O-nitric acid or zirconyl nitrate, and Mg (OH) ₂ to form an extrudable mixture. It was formed by mixing a colloidal silica suspension containing silica. Suitable colloidal silica suspensions are available from Columbia, Maryland, U.S.A. S. A. W. R. Grace and Co. Available under the trade name LUDOX® TMA. The composition was then extruded and had a diameter of about 3 mm. The extruded sample was dried and fired as in Example C above.

Isomerization catalyst G included MgO, SiO ₂ , and Laponite® clay. SiO ₂ was present in an amount of about 10% by weight and Laponite® clay was present in an amount of about 10% by weight. Laponite® was provided as a powder and mixed with Mg (OH) ₂ . A colloidal silica suspension containing 30% by weight silica suspended in water was added to additional water to make an extrudable mixture. Suitable colloidal silicas are described in Columbia, Maryland, U.S.A. S. A. W. R. Grace and Co. Available under the trade name LUDOX® AS-30. The composition was then extruded and had a diameter of about 3 mm. The extruded product was dried and fired in the same manner as Sample C above.

Isomerization catalyst H comprised MgO and Laponite® clay present in an amount of about 10% by weight. Isomerization catalyst H was formed by mixing Laponite®, which was powdered, with Mg (OH) ₂ before adding water. Water was then added to the Laponite® and Mg (OH) ₂ mixture to create an extrudable mixture. The composition was then extruded and had a diameter of about 3 mm. The extruded product was dried and fired in the same manner as Sample C above.

Isomerization catalyst I included MgO, ZrO ₂ , and Laponite® clay. Isomerization catalyst I was formed by dry mixing Laponite® with Mg (OH) ₂ provided that it was a powder. A solution of zirconium carbonate containing 20.3% by weight ZrO ₂ and additional water was added to form an extrudable mixture. The ZrO ₂ solution employed for the isomerization catalyst I was obtained from Magnesium Elektron Ltd. of Manchester, UK. Available under the trade name BACOTE®. Isomerization catalyst I was extruded and had a diameter of about 3 mm. The extruded product was dried and fired in the same manner as Sample C above.

Isomerization catalyst J contained MgO, talc, and the SiO _2. Talc, a colloidal silica solution containing 30 wt% silica, Mg (OH) ₂ , and water were mixed to form an extrudable mixture. Suitable colloidal silicas are those described in Golumbia, Maryland, U.S.A. S. A. W. R. Grace and Co. Available under the trade name LUDOX® AS-30. Talc was obtained as a powder from Aldrich chemicals and added to the magnesium hydroxide powder before the addition of the silica solution. The composition was then extruded and had a diameter of about 3 mm. The extruded product was dried and fired in the same manner as Sample C above. The final composition of the extrudate contained 80% MgO, 10% SiO2, and 10% talc.

  The fragment crush strength of each of the isomerization catalysts AJ was determined by placing each catalyst between two dies having an area of 3 mm width. A compressive load was applied and the force required to crush the piece was measured by a force transducer. The fragment crushing strength of each of the isomerization catalysts A to J is shown in Table 1. If the crush strength or unused isomerization rate was insufficient, the sample was not further tested for isomerization rate.

The isomerization rate for each of the isomerization selective catalysts AJ was measured when each catalyst was not used and after aging. The isomerization performance of each catalyst was measured at ambient pressure, using 1-butene, present in nitrogen in an amount of 20% by weight, as feed gas at a weight space velocity per unit time of 220 ° C. and 45 h ^−1. did. Unused isomerization performance was measured on the stream after 1 hour. After measuring the isomerization performance of each catalyst when not in use, each of catalysts AJ was then aged by calcining at 650 ° C. for 24 hours in a muffle furnace. The post-aging performance or performance of each of the isomerization catalysts AJ was tested after 1 hour aging on the stream. The results are provided in Table 1 and are shown along with the fragment crush strength of each of the isomerization catalysts AJ in the graph of FIG.

  As is apparent from FIG. 1, isomerization catalysts (eg, isomerization catalysts G, H, and I) containing metal silicate clay binders had improved crush strength over other catalysts. In addition, isomerization catalyst I, which contained both a metal silicate clay binder and a stabilizer, exhibited unused and post-aging isomerization activity similar to existing MgO tablets.

  Reference throughout this specification to "one embodiment", "an embodiment", "one or more embodiments" or "one embodiment" refers to a particular feature, structure, or structure described in connection with the embodiment. , Material, or feature is included in at least one embodiment of the invention. Thus, the appearance of phrases such as “in one or more embodiments”, “in one embodiment”, “in one embodiment”, or “in one embodiment” in various places throughout this specification The same embodiments of the invention are not necessarily shown. Furthermore, the particular properties, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments.

  Although the invention herein has been described with reference to certain embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention. It will be apparent to those skilled in the art that various modifications and variations can be made to the method and apparatus of the present invention without departing from the spirit and scope of the invention. Thus, it is intended that the present invention include modifications and variations that are within the scope of the appended claims and their equivalents.

Claims (18)

Extrusion comprising MgO in the range of 0.1% to 90% by weight, metal silicate clay binder in the range of 1% to 20% by weight, and ZrO ₂ in the range of 1% to 20% by weight. An isomerization catalyst that exhibits a fragment crush strength of at least 0.91 kg / mm (2.0 lbs / mm) and exhibits an unused isomerization rate and post-aging performance after aging at 650 ° C. for 24 hours; An extrusion isomerization catalyst characterized in that the post-aging isomerization rate is at least 50% of said unused isomerization rate. The extrusion isomerization catalyst according to claim 1, wherein MgO is present in an amount of at least 50% by weight. MgO is present in the range of 7 0 wt% to 9 0% by weight, extrusion isomerization catalyst according to claim 2. 4. Extrusion isomerization catalyst according to claim 3, wherein MgO is present in an amount of 80% by weight. ZrO ₂ is present in an amount ranging from 5 wt% to 1 5% by weight, extrusion isomerization catalyst according to claim 1. ZrO ₂ is present in an amount of 1 0% by weight, extrusion isomerization catalyst according to claim 5. The metal silicate clay binder comprises a layered grain child having a diameter and a thickness aspect ratio in the range of 25 to 50, extrusion isomerization catalyst according to claim 1. The extrusion isomerization catalyst of claim 7 , wherein the metal silicate clay binder comprises a synthetic metal silicate. The extrusion isomerization catalyst of claim 8 , wherein the synthetic metal silicate clay binder comprises synthetic hectorite. The extrusion isomerization catalyst of claim 1, wherein the metal silicate clay binder is present in an amount ranging from 5 wt% to 20 wt%. The extrusion isomerization catalyst according to claim 10 , wherein the metal silicate clay binder is present in an amount ranging from 8 wt% to 12 wt%. 12. Extrusion isomerization catalyst according to claim 11 , wherein the metal silicate clay binder is present in an amount of 10% by weight. The extrusion isomerization catalyst of claim 1, wherein the unused isomerization rate and the post-aging isomerization rate comprise a rate of 1-butene to 2-butene isomerization . A method of forming a 1-butene isomerization catalyst comprising:
MgO source, metal silicate clay binder, and a mixture of ZrO ₂ precursor, to form a first mixture,
Adding water to the first mixture to form a second mixture; and extruding the second mixture to form a single piece of at least 0.91 kg / mm (2.0 lbs / mm) Forming an extrudate exhibiting crushing strength and exhibiting an unused isomerization rate and post-aging performance after aging at 650 ° C. for 24 hours, wherein the post-aging isomerization rate is said unused isomerization A method characterized in that it is at least 50% of the speed. The MgO source, metal silicate clay binders, and ZrO ₂ precursors are dry mixed, the method of claim 14. The ZrO ₂ precursors is provided in solution form, The method of claim 14. The method of claim 16 , wherein the ZrO ₂ precursor is selected from one of zirconium carbonate, zirconium acetate, zirconium nitrate, and combinations thereof. 15. The method of claim 14 , wherein the metal silicate clay binder is present in an amount ranging from 5 % to 20% by weight.

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